"It is widely regarded by experts as the most powerful and technologically advanced air defense system in the world," and its deployment in Syria sends a powerful statement, said Sleboda.

"This is a very powerful defensive statement from Russia … very soon there will be a quite effective Russian no-fly zone over almost the entirety of Syrian territory, certainly covering all west of Syria, and very far towards the eastern border."

The deployment of S-400 is in addition to the Pantsir-S1 air defense missile-gun system the Russian air force already had at its disposal at the Hmeymim airbase, while the Moskva guided missile cruiser was already in the area.

"There wasn't really a need for them (the more powerful S-400 system)," said Sleboda.

"ISIL, of course, doesn't have an air force. They were simply a standard military precaution for an air mission. But now with the threat of NATO planes taking down Russian jets out of the air, that suddenly becomes a very real necessity."

On Wednesday the Russian defense ministry announced that the S-400 defense missile system will be deployed to its air base in Syria.

It can destroy tactical ballistic missiles at a range of up to 60 km, and air targets including cruise missiles and aircraft flying at a speed of up to 4800 meters a second, and a distance of up to 250 km. The S-400 is also capable of tracking and launching against most stealth technology.

promotes the use of narcotic / psychotropic substances, provides information on their production and use;

contains links to viruses and malicious software;

is part of an organized action involving large volumes of comments with identical or similar content ("flash mob");

“floods” the discussion thread with a large number of incoherent or irrelevant messages;

violates etiquette, exhibiting any form of aggressive, humiliating or abusive behavior ("trolling");

doesn’t follow standard rules of the English language, for example, is typed fully or mostly in capital letters or isn’t broken down into sentences.

The administration has the right to block a user’s access to the page or delete a user’s account without notice if the user is in violation of these rules or if behavior indicating said violation is detected.